Dry cell



Ja'nf1, 1939. 'c R, NES 2,143,245

DRY CELL Filed Oct. 2, 1951 INVENTOR Y C L/'nes www@ ATTORNEYS Patented Jan. A10, 1939 UNITED STATE vPsa-rem FFME 'i cierro. y (ci 13o-13s) This invention relates kto dry celled and more particularly to' an improved end closure therefor. In carrying out my invention I provide an end closure disc of insulating material having a metal g contact cap permanently secured thereto. They disc may be molded from plastic'orresinous ma.

terlals, such as phenolic condensation products or the like with the cap incorporated inthe disc at the time of molding, or the disc may fbe w stamped from sheet material and the cap insertedin. a central opening and spun or pressed into place.

The disc is employed in conjunction with a washer adapted to be seated on a circumferential i `l'i'idge or bead ,arranged close to the mouth of the can. The disc is placed over the washer and the edges of the can crimped or spun over the periphery oi the disc to hold it in place. Adjecent the periphery the disc is offset so that the' *2c central portion thereof isspaced from the adjacent washer. The contour of the surface of the disc produces a. cell having a pleasing appearance and it also provides a construction inwhich a straight edge or plane surface arranged on one es of the cell terminals is prevented from contacting with the other terminal of the cell. This tends to prevent accidental short-circuiting of the cell. in the accompanying drawing I have shown one form of the invention. In the drawing, so Fig. l is a central. longitudinal, sectional view of a cell constructed in accordance with my invention; and

Fig. 2 is a similar view of the closure disc with the contact cap placed in the disc prior to press- 35 ing or spinning it into integral relation with the disc Y Referring to the drawing, the reference numeral i designates a zinc can which forms one of the electrodes of the cell and which may be formed 40 of seamless drawn zinc in the usual manner. Adjacent the top the can is provided with an inwardly projecting circumferential bead or ridge t. The cellis provided with the usual core consisting ol a carbon pencil 3 and a surroimding de- 45 polarizing mixture, preferably formed of carbonaceous material and manganese dioxide as is in cell constructions.v An insulating disc or washer 6 is placed on the bottom of the core to insulate the positive terminal from the zinc so can. A suitable electrolytic paste i surrounds the core and extends slightly above the top of the core in the usual manner. In assembling-the cell the electrolyte solution is poured in the empty zinc can and the preformed core then placed in i the can causing the solution to rise to the properV level. A dat insulating washer 1 is then placed on the bead or ridge E. This washer is provided with a central opening through which the carbon pencil 31s adapted to project. The washer serves .to centralize the core and to retard evaporation of the electrolyte solution during the period in which the solution sets to form a paste.

In completing the cell construction I employ an end closure discs which, as stated, may be moldedof suitable plastic materialor stamped 10 from sheet material. The closure disc is pro- -vided with a. central opening adapted to receive a .pencil when the closure disc is in position as shown in Fig. l of the drawing. Adjacent the periphery of the disc it is provided with an olf-set or ange'lll arranged in a plane below the body portion. When the disc is formed of sheet material, the cap 's is inserted in a central opening as shown in Fig. 2 of the drawing and the skirt 20 ii of the cap is then spun or pressed to produce an outwardly flared lower end i2 shown in Fig. 1

of the-drawing which forms au integral structure of the closure disc and cap. This also bulges or mushrooms the upper portion of the cap formg5 ing a constricted central portion i3 which frictionally engages the carbon pencil and securely anchors said cap to the insulating disc. When the closure member 8 is molded from plastic material, the skirt Il of the capV is preformed into the-shape shown in Fig. l of the drawing to f provide the dared end i2 and the constrlcted centrai portion I3. The preformed disc is placed in the cell with the carbon pencil 3 arranged in the m'etal contact cap S as shown and the upper 35 edge of the can is then crimped over the flange lil of the disc as indicated at'll. This provides a space i5 between the body portion 8 of the closure member and the washer l. As the washer l does not form a gas tight t around the carbon 40 pencil 3, the space i5 communicates with and forms an enlargement of the usual gas space at the top o! the cell.

The advantages of .the described construction will be apparent to those skilled in the art. The

structure for the cell which prevents a straight edge or plane surface lying over the cell from contacting with the two cell terminals and thus short-circuitinr the cell. It will be seen from an inspection of Fig. 1 of the drawing that anything lying on the cell so as to engage the cap 9 will contact with the closure member adjacent the outer edge of the body pnrtion 8 but will not be in contact with the zinc can. Similarly a lo straight edge touching the zinc can will engage the cuter portion of the body member 8 of the closure disc and will extend over the cap 9 out of contact therewith.

I claim:

l l. A dry cell comprising a zinc can, a carbon 25 aflaring skirt forming a constricted central portion engaging said carbon pencil, said skirt forming an exterior groove embracing said insulating disc.

2. A dry cell having a carbon electrode, and an 30 end closure comprising a disc of insulating material having a central opening, and a sheet-metal contact cap having a depending shirt, the shirt being shaped to form an inner constricted portion and an external groove, the central opening of said disc being received in said groove to form a unitary closure member, and the carbon electrode being received in said constricted portion of said skirt to anchor said closure member to said electrode.

3. A dry bell comprising a zinc can, a carbon. electrode arranged in said can, and an end closure comprising a .preformed disc of insulating inaterial, having a peripheral ange arranged in a plane below the central portion of said disc, the

upper edge of said can being crimped over the periphery of said flange, and a contact cap carried by the central portion of said disc and engaging said carbon electrode, the upper edge of saidv can being below the surface of the central so portion of said disc whereby a straight line connecting the .cap and the edge of said can passes through said disc.

4. A dry cell comprising a zinc can. a carbon electrode arranged in said can, an inwardly extending circumferential bead formed adjacent the top of said can, a washer seated on said bead, and an end closure comprising a preformed disc of insulating material, having a peripheral ange arranged in a plane below the central portion of said disc the upper edge of said'can being crimped over the periphery of said flange, and a contact cap carried by the central portion of said disc and engaging said carbon electrode, the upper edge of said can being below the surface of the central portion of s aid disc whereby a straight line connecting the cap and the edge of said can passes through said disc.

5. In a dry cell having a metallic cup whereof the edge is exposed and a cartridge therein hav= ing an upwardly projecting central electrode, in combination, a preformed closure formed with an aperture to receive the projecting end of the central electrode, said closure being so formed that a line tangent to the electrode and the upper edge of the cup passes through the closure, whereby simultaneous contact of said electrode and cup by a plane surface is prevented.

6. In a dry cell having a metallic cup whereof the edgeis exped and a cartridge therein having an upwardly projecting central electrode, in combination, a preformed non-metallic closure formed with an aperture to receive the projecting end of the central electrode, said closure being so formed that a line tangent to the electrode and the upper edge of the cup passes through the closure, whereby 'simultaneous contact of said electrode and cup by a plane surface is prevented.

'1. In a dry cell, in combination, a closure lformed with a central aperture, a metallic cup whereof the edge is exposed and whereof the wall extends upwardly at least to the plane of the upper Asurface of the marginal portion of the closure, a cartridge in the cup having a. central electrode projecting upwardly through the aperture of the closure and material of the closure between the marginal portion thereof and the aperture being disposed sumciently above the plane of the marginal portion that a line tangent to the electrode and the upper edge of the cup passes through material of the closure whereby simultaneous contact of said electrode and cup by a plane surface is-prevented.

ormoni: R. Lmns. 

